Re: [PATCH v2 3/5] PCI: qcom: Add .get_ltssm() helper

[Manivannan Sadhasivam]

On Tue, Feb 17, 2026 at 04:49:08PM +0530, Krishna Chaitanya Chundru wrote:
> For older targets like sc7280, we see reading DBI after sending PME
> turn off message is causing NOC error.
> 
> To avoid unsafe DBI accesses, introduce qcom_pcie_get_ltssm(), which
> retrieves the LTSSM state from the PARF_LTSSM register instead.
> 

You completely missed describing the helper here and where it is used.

> Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 67a16af69ddc75fca1b123e70715e692a91a9135..2c4dc7134e006d3530a809f1bcc1a6488d4632ad 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -131,6 +131,7 @@
>  
>  /* PARF_LTSSM register fields */
>  #define LTSSM_EN				BIT(8)
> +#define PARF_LTSSM_STATE_MASK			GENMASK(5, 0)
>  
>  /* PARF_NO_SNOOP_OVERRIDE register fields */
>  #define WR_NO_SNOOP_OVERRIDE_EN			BIT(1)
> @@ -1255,6 +1256,15 @@ static bool qcom_pcie_link_up(struct dw_pcie *pci)
>  	return val & PCI_EXP_LNKSTA_DLLLA;
>  }
>  
> +static enum dw_pcie_ltssm qcom_pcie_get_ltssm(struct dw_pcie *pci)
> +{
> +	struct qcom_pcie *pcie = to_qcom_pcie(pci);
> +	u32 val;
> +
> +	val = readl(pcie->parf + PARF_LTSSM);

Newline

- Mani

-- 
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